<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>罗马变数字</title>
</head>

<body>

</body>
<script>
    /*  var str='987'
     str.slice(1)
     console.log(str);
     console.log(str.slice(1));
     str.substring(1)
     console.log(str); */
    function romanToNum(s) {
        for (var i = 0; i < s.length; i++) {
            // console.log(1);
            // console.log(i);
            s = s.slice(i, 1)
            console.log(s);
            // s=s.slice
        }
    }

    romanToNum('9999')
</script>

</html>